AUTHOR=Kabir Firoza , Hosen M. Mofazzel , Ding Xiaxin , Lane Christopher , Dhakal Gyanendra , Liu Yangyang , Dimitri Klauss , Sims Christopher , Regmi Sabin , Sakhya Anup Pradhan , Persaud Luis , Beetar John E. , Liu Yong , Chini Michael , Pathak Arjun K. , Zhu Jian-Xin , Gofryk Krzysztof , Neupane Madhab 

TITLE=Effect of Dilute Magnetism in a Topological Insulator

JOURNAL=Frontiers in Materials

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2021.706658

DOI=10.3389/fmats.2021.706658

ISSN=2296-8016

ABSTRACT=<p>Three-dimensional (3D) topological insulator (TI) has emerged as a unique state of quantum matter and generated enormous interests in condensed matter physics. The surfaces of a 3D TI consist of a massless Dirac cone, which is characterized by the Z<sub>2</sub> topological invariant. Introduction of magnetism on the surface of a TI is essential to realize the quantum anomalous Hall effect and other novel magneto-electric phenomena. Here, by using a combination of first-principles calculations, magneto-transport and angle-resolved photoemission spectroscopy (ARPES), we study the electronic properties of gadolinium (Gd)-doped Sb<sub>2</sub>Te<sub>3</sub>. Our study shows that Gd doped Sb<sub>2</sub>Te<sub>3</sub> is a spin-orbit-induced bulk band-gap material, whose surface is characterized by a single topological surface state. Our results provide a new platform to investigate the interactions between dilute magnetism and topology in magnetic doped topological materials.</p>